Boiler feed water heating plant



Feb. 6, 1934. L QUTZ BOILER FEED WATER HEATING PLANT Filed Deo. l, 1951 Ccm'ne Lou' "NVENTOR,

gx Mturney,

Patented Feb. 6, 1934 PATENT ortica BOILER FEED WATER HEATING PLANT camille Loutz, Mulhousl Societe Alsacienne De ques, Mulhouse, France e, France, assignor to Constructions Mecani- Application December 1, 1931, Serial No. 578,295, and in France December 13, 1930 rclaims. (o

The invention relates to feed Water heating plants for steam generators and more particularly to feed water heaters adapted to be heated.H by combustion gas from the hearth.

When the feed water heatingcoils are arranged in a region where the combustion gases which escape to the stack are still very hot a failure of the feed water pump may bring about an overheating of the coils and Very serious deteriorations.

One object of the invention consists in the provision of safety or emergency means for compensating a failure or deficiency of the feed water Another object is to devise an improved arrangement for the feed water purifier and steam separator.

Further objects and advantages of the invention will be apparent from the following description with reference to the appended drawing, in which:

Fig. 1 is a vertical section on the line 1-1 of Fig. 2 of a portion of a steam generating plant embodying my invention.

Fig. 2 is a partial cross-section `on the line 2-2 of Fig. 1.

Fig. 3 is a horizontal section on of Fig. 1.

Figs. 4 and 5 show in two different positions respectively the double valve arranged at the in- ,let of the heating and vaporizing section.

, Referring to the'drawing, 1 denotes a steam and water upper drum supported by la suitable brickwork 20 above a combustion chamber 21. The steam space of said upper drum is connected with a lower water drum 10 through inclined vaporizing tubes 22 and the water space of the upper drum is connected with drum 10 through upright water feeding tubes 23. Tubes 22-23 are located in the path followed by the combustion gases from chamber 1 toward the stack through the gas flue 2.

A by-pass flue 24, provided with a damper 25, serves to control the flow of gas through the iiue 2.

Arranged within iiue 2 are the inlet section 3 and middle section, 4 of the feed water heating unit, which form together what I call the preheating section, connected with the heating and -vaporizing section 5, arranged below the upper drum of the boiler, in contact with the hottest gas.

y The feed water is delivered by a pump 26, from a pipe 27, to the inlet section 3 comprising horizontal coils, as shown in Fig. 2. These coils, which are in contact with'cooled gas and are thus conthe une 3-3 stantly covered with condensed water containing carbon dioxide, sulphur dioxide, etc., are rapidly corroded and must be frequently renewed. For this reason, they are separated from the middle coils 4 and are mounted in a readily removable manner.

Coils 3 are connected with the coils 4 of the middle section, which are similar to coils 3 but are preferably mounted in the usual, non-removable manner, since they are subjected to a less `severe corrosion than coils 3.

The outlet of coils 4 is connected with a gas separator and settling tank 28, having a gas exhaust valve 29 and a draining cock 30 for the mud. Its upper part is connected through a pipe 31 with the heating and vaporizing section of the feed water heating unit. Section 5 includes a number of vertically arranged coils opening at their lower part into a lower header and at their upper part into vertical tubes '7, which extend through the upper drum 1 into a settling purifying chamber 6, whose bottom leads to a compartment 32 of the upper drum 1, a wall of said compartment forming an overflow weir 33. Tubes 7 Y are provided, below the lower level of the water in drum 1, with suitable holes 8. A check valve 11 in pipe 31 prevents the steam pressure from being transmitted to the settling tank 28.

In operation, the combustion gas follows the path indicated by the arrows, while the feed water supplied by pump 26 circulates upwardly through the parts 3, 4, 28, 3l, 5, 7, 6, 32, then overflowing over weir 33 into the main compartment of drum 1. 4

In the lower and middle sections 3 and 4, which are in contact with gas already cooled, the solid matters precipitate and are driven by the flow of water into the settling tank 28 where they settle and may be drained 01T. Any gas disengaged by the heat escapes through valve 29. The preheated water then proceeds into the vaporizing section 5, in contact with very hot gas. The water is partially vaporized, the mixture of water and steam flowing upwardly through tubes 7 into chamber 6, where the steam separates from the water, the disengagement being facilitated by the arrangement of the bottom of chamber 6. Compartment 32 provides for a further separation of mud and, as the water proceeds above partition 33, the separation of steam is achieved. Mud may be removed from compartment 32 through a draining cock 35.

It will be noted that the parallel arrangement and vertical disposition of coils 5 provide for the l ready and free circulation of the Water-steam mixture, which has a greater specific volume than water. Besides, the rate of circulation through coil is reduced, thus furthering the vaporization.

5 If, for any reason, the pump 26 fails or is decient, water flows from drum 1 through holes 8 andgiipes 7 into coils 5, thus cooling the coils 5 and preventing an emptying and subsequent overheating and deterioration of the latter. I have 10 thus provided an efficient safety or emergency means in the case of a stopping in the feed water circulation. j,

The above means may be found insufficient in some cases, and provision may be made of aux-Y iliary means for supplying the coils 5 with Water. As illustrated, pipe 31 may be connected to a tube 9, opening into drum 1, below the lower water level, or to a tube 9', opening into the lower drum 10, or to both tubes 9 and 9', Water flowing from drum 1 and/or 10 through tube 9 and/or 9 into the-coils 5. A check valve 12 is arranged on tube 9 and/ or' for preventing the feed-Water forced by pump 26 from getting directly into the;

boiler, without flowing through coils 5, said valve allowing'the flow of water fromY tube 9 or 9' toward coils 5 by the effect of the static head in said tubes. 1

Check-valves 11, 12 may be formed into an integral double valve 13, as shown in Fig. 4, 13 de- 30 noting the double valve and 34 the conduit leading to the lower heater of section 5. In the pcsition shown in Fig. Li, the delivery pressure of pump 26 forces the double valve to the left thus clearing the way of the feed-water toward section 5. In theposition'shown in Fig. 5'; where the pump is idle or deficient, the head of water i forces the double-valve to the right, thus clearing the way of the water contained in the boiler toward section 5.

The valves 11, 12 or the double-valve 13 may be biased; if need be, in the required direction, by springs, counterweights, or the like.

The arrangement of the double-valve may be such that it moves from the position shown in Fig. 4 to the position of Fig. 5 as soon as the pressure of delivery of pump 26 falls below any predetermined valuc. Y

Although the construction above described is what I consider as a preferred embodiment of my invention, many changes maybe made Without departing from the scope thereof.

Having now described my invention what I claim as new and desire to secure by Letters Patent is:

1. In a boiler feed water heating plant, a steam and water drum, a feed water heater placed at a lower level than said drum, means for forcing water through said heater into said boiler, a tube connecting said feed water heater with said drum,

'60 said tube extending through the water space and lopening in the steam space of said drum, a hole in said tube, said hole being disposed in the portion of the tube within the water space of said drum, whereby the water is permitted to flow back from the drum into said heater if the Water forcing means failed or were decient.

2. In a boiler feed water heating plant, a steam and water drum, a feed water heater placed at a lower level than said drum, means for forcing water through said heater into said boiler, a steam separator in the steam space of said drum, a tube connecting said feed water heater with said drum,

said tube extending through the waterspace and opening in said steam separator, a hole in vsaid tube, said hole being disposed in the portionof the tube Within the water space of said drum, whereby the water is permitted to flow back from the drum into said heater if the water forcing means failed or were decient.

Y3. In a boiler fee-:l Water heating plant, a steam and waterYdrum, a feed Water heater placed at a lower level than said drum, the last portion of which being composed of a number of parallel arranged tubes, said tubes extending through the Water space and Yopening in the steam space of said drum, means for forging water through said heater into said boiler, and holes in said tubes disposed inthe portion of the tube within the water;

space of said drum, whereby the water is permitted to flow back from the drum into said heater if the water forcing means failed or were deficient.

4. In a boiler feed water heating plant, a steam and water drum, a feed water heater placed at a lower level than said drum, the last portion of which being composed of a number of parallel are ranged tubes and disposed below the water level in said drum, said tubes extending through the Water space and opening in the steam space of said drum, means for forcing water through said heater into said boiler, and holes in said tubes, said holes being disposed in the portion of the tube within the Water space of said drum, whereby the water is permitted to ow back from the drum into said heater if the water forcing means failed or were deficient. g

5. In a boiler feed Water heating plant, a steam and water drum, a steam separator in the steam space of said drum, a feed water heater placed at a lower level than said drum, the last portion of which is composed of a number of parallele arranged tubes, said tubes extending through the water space of said drum and opening into said steam separator, means for forcing water through said heater into said boiler, and holes in said tubes, said holes being disposed in the portionY of the tube within the water space of said drum, whereby the water is permitted to now back from the drum into said heater if the water forcing means failed or were deficient.

6. In a boiler feed water heating plant a steam and Water drum,'a steam separator in the steam space of said drum, saidsteam separator having an inclined bottom, a vertical wall in said drum vbelow said bottom, arranged to form a settling compartment below the lower edge of said bottom and a Weirfor the water overflowing from said settling compartment tov the remainder of said drum, a draining cock connected to said settling compartment, a feed water heater, the last portion of which is composed of a number of parallel arranged tubes, `said tubes extending through the water space of said drum and opening into said steam separator.

7. Ina feed water heating plant, a boiler, a combustion chamber, a gas flue connected with said chamber, a feed water heater ccmprising and the water space, anotherv check Vvalve on said direct connection, and means for operatively connecting said two valves in order that one of said Yvalves isv closed when the other is opened.

CAMILLE LOUTZ. 

